# Greg

Popular questions and responses by Greg-
## physics

A hypodermic syringe contains a medicine with the density of water (figure below). The barrel of the syringe has a cross-sectional area of 2.44 10-5 m2. In the absence of a force on the plunger, the pressure everywhere is 1.00 atm. A force vector F of

*asked on March 28, 2012* -
## Math

A man has 2 pennies, 3 nickels, 1 dime and 2 quarters. How many different sums of money can he make using one or more of these 8 coins?

*asked on May 5, 2011* -
## PHYSICS

Fig. 6-48 shows a conical pendulum, in which the bob (the small object at the lower end of the cord) moves in a horizontal circle at constant speed. (The cord sweeps out a cone as the bob rotates.) The bob has a mass of 0.038 kg, the string has length L =

*asked on March 1, 2008* -
## stats

Find the probability of at least 2 girls in 10 births. Assume that male and female births are equally likely and that the births are independent events.

*asked on March 16, 2015* -
## Photography

The overall impact of all of a photographs features is called what? A. Unity** B. Structure C. Aesthetic D. Emphasis

*asked on November 15, 2018* -
## Math

If a baseball player has a batting average of 0.420, what is the probability that the player will get at least 2 hits in the next four times at bat?

*asked on February 28, 2016* -
## Difficult Trig Word Problem

The displacement of a spring vibrating in damped harmonic motion is given by y(t) = 4e^-3t sin(2pi*t) where y = displacement and t = time with t greater than/equal to zero. Find the time(s) when the spring is at its equilibrium position (y=0). The number

*asked on November 14, 2012* -
## AP Physics

A pole-vaulter approaches the takeoff point at a speed of 9.50 m/s. Assuming that only this speed determines the height to which he can rise, find the maximum height at which the vaulter can clear the bar.

*asked on November 13, 2010* -
## TRIG help quickly please

Mark any solutions to the equation 2cos2x - 1 = 0. The answer can be more than one. Thank you π/8 -7π/4 15π/4 3π/4

*asked on January 14, 2014* -
## math - calc

A conical water tank with vertex down has a radius of 12 feet at the top and is 26 feet high. If water flows into the tank at a rate of 30 {\rm ft}^3{\rm /min}, how fast is the depth of the water increasing when the water is 12 feet deep?

*asked on October 1, 2013* -
## Precalculus

Find the distance along an arc on the surface of the earth that subtends a central angle of 1 minute. (1 minute = 1/60 degree) This is a nautical mile. Note that the radius of the Earth is 3960 miles and there are 1760 yards in a mile. Express your answer

*asked on September 10, 2012* -
## Math

A rectangular swimming pool is bordered by a concrete patio. The width of the patio is the same on every side. The area of the surface of the pool is equal to the area of the patio. What is the width of the patio? (Length of Pool: 24 Width of Pool: 16)

*asked on February 3, 2016* -
## Algebra (Please check)

PLEASE CHECK MY ANSWERS (: I just want to make sure I am doing this correctly __________________________________ Graph the system of constraints and find the value of x and y that maximize the objective function. Constraints: x ≥ 0 y ≥ 0 y ≤ (1)/(5)

*asked on September 17, 2012* -
## Algebra 2

How would I find the sum of the geometric series given? 1/5 - 1/25 + 1/125

*asked on May 12, 2012* -
## Math

A swimming pool is 40 feet long, 20 feet wide, 8 feet deep at the deep end, and 3 feet deep at the shallow end; the bottom is rectangular. If the pool is filled by pumping water into it at the rate of 40 cubic feet per minute, how fast is the water level

*asked on March 2, 2012* -
## Statistics

A study of 40 bowlers showed that their average score was 186. The standard deviation of the population is 6. Find the 95% confidence of the mean score for all bowlers.

*asked on April 27, 2019* -
## Calculus

A rectangular box with a square base and cover is to have a volume of 2500 cubic feet. If the cost per square foot for the bottom is $2, for the top is $3, and for the sides is $1, what should the dimensions be in order to minimize the cost?

*asked on December 10, 2017* -
## Math

An object is projected directly upward from the ground. Its distance in feet from the ground in t seconds is s equals s=112t−16t^2 The object will be 160 feet from the ground after () second(s) and after () second(s). The object strikes the ground

*asked on April 18, 2016* -
## Math

Find the adjusted balance due at maturity for a 90 day note of $15000 at 13.7% ordinary interest if a partial payment of $4000 is made on the 60th day of the loan.

*asked on January 27, 2015* -
## chemistry

10. If the calcium oxide were obtained by the heating of calcium hydroxide, how much hydroxide would be needed to obtain the 15.0 g? 11. If the 15.0 g of calcium oxide in the above problems were allowed to react with water, what amount of calcium hydroxide

*asked on December 13, 2012* -
## calculus

Consider the function f(x)=12x^5+30x^4–160x^3+5 . f(x) has inflection points at (reading from left to right) x=D , E , and F D= E= F=

*asked on November 25, 2008* -
## math

The amount of money in an account with continuously compounded interest is given by the formula A = Pert, where P is the principal, r is the annual interest rate, and t is the time in years. Calculate to the hundredth of a year how long it takes for an

*asked on April 22, 2007* -
## algebra

A math class has a total of 47 students. the number of females is 17 less than the numberof males. how many males and how many females are in class?

*asked on February 8, 2015* -
## Chemistry

How many electrons will each element gain in forming an ion? a. Nitrogen ______ b. Oxygen ________ c. Sulfur _______ d. bromine _______

*asked on October 9, 2012* -
## English

Hamlet: I need to look at the passages from Acts IV and V and assess their impact within the context of the whole play. I have already done so and it's giving me these questions using a passage. I need some help, please. :) Passage 1: " Now, whether it be

*asked on November 30, 2009* -
## Astronomy

What part of the Solar System are you most interested in learning about?

*asked on February 11, 2020* -
## physics

An electrical device contains a transformer. Its primary coil has 200 turns, and its secondary coil has 20 turns. If the device is plugged into a 120-volt line, what is the output voltage of the device?

*asked on November 2, 2015* -
## Physics

An auditorium has dimensions 10m x 10m x 60m. How many moles of air fill this volume at STP? I'm stumped.

*asked on December 3, 2014* -
## Precalc/Trig Word Problem

From the top of a 200-ft lighthouse, the angle of depression to a ship in the ocean is 23 degrees. How far is the ship from the base of the lighthouse?

*asked on October 8, 2012* -
## Precalc/Trig 1

What equation would you use to show that the point ((square root of 11)/(6), (5/6))is on the unit circle?

*asked on October 8, 2012* -
## Precalculus

he distance between 2 points (x1,Y1) and (x2,y2) is given by d = square root (x1-x2)^2 + (y1-y2)^2 a - pick 2 arbitrary points in 3 dimensions, (x1, y1, and Z1) and (x2,y2,z2) and plot these points. Not that there are 90 degrees between the xy, xz, and yz

*asked on September 14, 2012* -
## Physics

A ball initially moving at 0.5m/s rolls down a straight slope, accelerating at 0.25m/s^2 for 4 sec, how far does the ball travel in this time?

*asked on June 16, 2011* -
## math

a rectangular parking lot has a length that is 10 yards greater than the width. the area of the parking lot is 200 square yards.find the length and the width

*asked on February 5, 2011* -
## math

could someone show me how to write this or set up this equation?2 ships sail from the same port, one sails dew east at 15 mph and the second sailed dew south at 20 mph, how far apart are the ships after 3 hours?

*asked on October 19, 2010* -
## Math

2+3 add each number to itself plus one

*asked on September 26, 2016* -
## Check Answers Quick -Physics

What causes the centripetal acceleration of an electron in a hydrogen atom? electrical attraction gravity friction

*asked on December 16, 2013* -
## chemistry science

substrate concentration= 3.5mM (c2) buffer=0.4 ml 10mM PNPP stock= ?ml (V1) water=?ml enzyme= 0.2ml total volume =1ml (V2) I need help with a dilution, I understand that you would be using c1v1=c2v2 but im confused as to what we need to find the amount of

*asked on October 1, 2013* -
## Math

Suppose the quantity demanded per week of a certain dress is related to price by the demand equation p=√75-2x. In order to maximize revenue, how many dresses should be made and sold each week?

*asked on May 6, 2013* -
## chem

Given that Ka for HClO is 4.0 × 10-8 at 25 °C, what is the value of Kb for ClO– at 25 °C? Given that Kb for CH3CH2NH2 is 6.3 × 10-4 at 25 °C, what is the value of Ka for CH3CH2NH3 at 25 °C?

*asked on March 26, 2013* -
## Chemistry

Can someone pls help me!! You decide to establish a new temperature scale on which the melting point of ammonia (-77.75 C ) is 0 A, and the boiling point of ammonia (-33.35 C ) is 200 A. What would be the boiling point of water in A ? What would be the

*asked on February 2, 2013* -
## Physics

A thin, uniform rod is hinged at its midpoint. To begin with, one half of the rod is bent upward and is perpendicular to the other half. This bent object is rotating at an angular velocity of 6.8 rad/s about an axis that is perpendicular to the left end of

*asked on November 17, 2012* -
## Chemistry

For the reaction IO3– + 5I– + 6H+ 3I2 + 3H2O the rate of disappearance of I– at a particular time and concentration is 2.8 x 10-3 M s-1. What is the rate of appearance of I2 in molarity per second?

*asked on July 31, 2012* -
## physics

A crate of weight Fg is pushed by a force on a horizontal floor. (a) If the coefficient of static friction is μs, and is directed at angle θ below the horizontal, show that the minimum value of P that will move the crate is given by the following

*asked on October 17, 2011* -
## Physics

An electron is at the origin. (a) Calculate the electric potential VA at point A, x = 0.410 cm. (b) Calculate the electric potential VB at point B, x = 0.820 cm. What is the potential difference VB - VA?

*asked on February 18, 2011* -
## algebra

find the x and y intercepts: f(x)=-x^2 +3x+10

*asked on June 3, 2010* -
## ECON

CAN ANYONE PLEASE HELP// 1. In the Country of Wiknam, the velocity of money is constant. Real GDP grows by 5 percent per year, the money stock grows by 14 percent per year, and the nominal interest rate is 11 percent. What is the real interest rate? 2. The

*asked on October 23, 2007* -
## econ--HELP!!

QUESTION Consider an economy described by the following equations: Y=C+I+G Y=500 G=1,000 T=1,000 C=250+0.75(Y-T) I=1,000-50r a.In this economy, compute private saving, public saving, and national saving. b. Find the equilibrium interest rate. c. Now

*asked on October 21, 2007* -
## statistics

An English teacher needs to pick 10 books to put on her reading list for the next school year and she needs to plan the order in which they should be read. She has narrowed down her choices to 4 novels 8 plays, 5 poetry books, and 5 nonfiction books. If

*asked on February 10, 2019* -
## Science

How would you experiment to find out how much this plant type needs for optimal growth? I am not sure how to answer this question.

*asked on September 21, 2017* -
## math

Hi, I was working on my math homework and I was stumbling on these problems. I wanted to double check my answers that I have; I also could not answer 5. If vectors O(0,0,0), A(6,0,0), B(6,-sqrt(24), sqrt(12)), and C(0,-sqrt(24), sqrt(12)) form a square. 1)

*asked on April 19, 2017* -
## Math 11

write the equation in vertex form, of a parabola with vertex (5, -1) and that passes through the point (6, 8)

*asked on April 11, 2017* -
## Math

Katie is baking cookies. She only wants to make 3/4 of the recipe. She needs to take 3/4 of the 2/3 cup of sugar. How much sugar does she need?

*asked on January 24, 2017* -
## Math

How many 3/8 foot pieces of wood can you cut from a board that is 1 7/8 feet long?

*asked on August 22, 2016* -
## math

sonya spent 3/8 of her money and had $15 left. how much money did she orginally start with?

*asked on March 29, 2016* -
## Algebra

In 2009, a diabetic express company charged $39.95 for a vial of type A insulin and $30.34 for a vial of type B insulin. If a total of $2022.21 was collected for 60 vials of insulin, how many vials of each type were sold?

*asked on August 17, 2015* -
## statistics

In a certain lottery, five different numbers between 1 and 31 inclusive are drawn. These are the winning numbers. To win the lottery, a person must select the correct 5 numbers in the same exact order in which they were drawn. What is the probability of

*asked on March 16, 2015* -
## Physics College

What is the rate of deceleration of a 1400-kg SUV that is going 75.0 km/h and then slows to 25.0 km/h in 8.20 s?

*asked on September 30, 2014* -
## Physics Electricity and Magnetism

A microscopic droplet of ink in an ink-jet printer is deflected onto the paper by a force of 2.34×10-4 N. If the field causing the deflection is 6.62 kN/C, what is the charge on the droplet? What equation do I use to solve and What does each value mean in

*asked on August 29, 2014* -
## Chemistry

Consider the following reaction: CaCO3(s)→CaO(s)+CO2(g). Estimate ΔG∘ for this reaction at each of the following temperatures. (Assume that ΔH∘ and ΔS∘ do not change too much within the given temperature range.) A) 310K B) 1070K C) 1470K And is

*asked on May 14, 2014* -
## Science check answers please and quickly

1. Jim is doing a physics experiment on the rate of cooling of solid objects in air. Which of the following is a variable that is not directly part of his experiment, but should be controlled in his experiment? (Points : 1) initial temperature to which he

*asked on January 8, 2014* -
## calcullus

Suppose the quantity demanded per week of a certain dress is related to price by the demand equation p=√75-2x. In order to maximize revenue, how many dresses should be made and sold each week?

*asked on May 5, 2013* -
## Chem

How many kilojoules of energy are needed to convert 104 g of ice at -14.6 to water at 25.8°C? (The specific heat of ice at -14.6 is 2.01 J/g°C.)

*asked on April 4, 2013* -
## Critical Points, Etc.

find the values for a, b, and c such that the function f(x)= x^3 + ax^2 + bx+ c has a critical point at (1,5) and an inflection point at (2,3). a= -6 b= 3 c= 7 i got those, but they're wrong. i'm not sure why. :/

*asked on March 20, 2013* -
## Can someone Please Help

You decide to establish a new temperature scale on which the melting point of ammonia (-77.75 C ) is 0 A, and the boiling point of ammonia (-33.35 C ) is 200 A What would be the temperature of absolute zero in A ?

*asked on February 4, 2013* -
## Chemistry

You decide to establish a new temperature scale on which the melting point of ammonia (-77.75 C ) is 0 A, and the boiling point of ammonia (-33.35 C ) is 200 A. What would be the boiling point of water in A ? What would be the temperature of absolute zero

*asked on February 2, 2013* -
## Precalculus

Prove or disprove cos(x+y)cos(x-y)=cos squared (x) - Sin squared (x) I dstributed the cosines and attempted to cancel out terms but I can't get the signs right. Any help on what I am missing?

*asked on November 14, 2012* -
## Physics

A certain light truck can go around a flat curve having a radius of 150 m with a maximum speed of 29.0 m/s. With what maximum speed can it go around a curve having a radius of 88.0 m?

*asked on November 13, 2012* -
## phi 103

"If that wasn't illegal, then it wouldn't be against the law" may commit which fallacy?

*asked on October 23, 2012* -
## Calculus L'Hopital Rule

lim x->0 (x)sin(x)/1-cos(x). They both go to 0 so 0/0. now take L'H and product rule of top? lim x->0 (1)sin(x)+ cos(x)(x)/1-cos(x) what next? how do i solve from here?

*asked on October 18, 2012* -
## Chemistry

Write the symbol and electron configuration for each ion and name the noble gas with the same configuration. a. nitride _________________________ b. oxide ___________________________ c. sulfide _________________________ d. bromide _________________________

*asked on October 9, 2012* -
## Precalculus/Trig 5

Find the exact value of thet following trigonometric functions: tan(5pi/6) tan(7pi/6) tan(11pi/6)

*asked on October 8, 2012* -
## Precalculus/Trig 3

The degree measure of an angle theta is 40 degrees. What is the radian Measure of theta? at what point P does the terminal ray intersect the unit circle (what is the ordered paid P(____, ___)?

*asked on October 8, 2012* -
## Precalculus SOH CAH

how are the following relations true? S(theta + pi/2) = C(theta) and C(theta + pi/2) = -S(theta)?

*asked on September 22, 2012* -
## ALG 2 (exponents)

Write log'2' 8 = 3 in exponential form?

*asked on May 12, 2012* -
## media and american culture

Do you think the Internet has created more harm than good to artists in the music industry? Explain your answer.

*asked on December 1, 2011* -
## bca

____ is the code of acceptable behaviors users should follow while on the Internet; that is, it is the conduct expected of individuals while online.

*asked on March 1, 2011* -
## Physics

A 10kg particle undergoes simple harmonic motion with an amplitude of 2.0mm, a maximum acceleration of 8.0x10^3 m/s^2, and an unknown phase constant (phi) What are: a.) the period of the motion b.) the maximum speed of the particle c.) total mechanical

*asked on November 30, 2010* -
## Physics

A 10kg particle undergoes simple harmonic motion with an amplitude of 2.0mm, a maximum acceleration of 8.0x10^3 m/s^2, and an unknown phase constant (phi) What are: a.) the period of the motion b.) the maximum speed of the particle c.) total mechanical

*asked on November 30, 2010* -
## 11th grade

Use the following functions to solve. f(x) = x2 + x + 1; g(x) = 5 - 2x; h(x) = -x2 Solve f(g(-1))

*asked on October 20, 2010* -
## physics

In the diagram below, qA = 9.8 µC & qB = -1.4 µC. There is no charge at point C. The distance between A & C is 2.1 cm and the distance between B & C is 9.6 cm. Find the electric potential at point C

*asked on September 13, 2010* -
## English

I need help with this. “What is Hamlet ‘about’?” and “What are its enduring themes and messages?”. The responses you provide do not have to be governed by the Values and Worldviews (Dialectic) approach. Substantiate your own ideas with evidence

*asked on November 29, 2009* -
## Statistics

For df = 25, determine the value of A that corresponds to each of the following probabilites: a. P(t >- A)= 0.025 b. P(t

*asked on October 3, 2009* -
## Applied Math- Gr.11

A farmer wants to enclose three sides of a rectangular pasture unsing 1000 yards of fencing. The fourth side does not require fencing because it borders a river. What dimensions (length and width) should the farmer choose in order to enclose the greatest

*asked on May 1, 2008* -
## pre-Algebra

Write the following as a fraction and show your work. 0.83 (the three is repeating) I don't know how to do it with only one of the numbers repeating and it is not in my book.

*asked on December 11, 2007* -
## ECON-can anyone help

CAN ANYONE PLEASE HELP// 1. In the Country of Wiknam, the velocity of money is constant. Real GDP grows by 5 percent per year, the money stock grows by 14 percent per year, and the nominal interest rate is 11 percent. What is the real interest rate? 2. The

*asked on October 22, 2007* -
## ECON-HELP!!

1. In the Country of Wiknam, the velocity of money is constant. Real GDP grows by 5 percent per year, the money stock grows by 14 percent per year, and the nominal interest rate is 11 percent. What is the real interest rate? 2. The goverment raises taxes

*asked on October 21, 2007* -
## Science

Why can humans not survive on Venus? Thank you for using the Jiskha Homework Help Forum. You will find 2 answers above under "Science." Since the volunteers do not sit here 24/7, a half hour is not long enough to wait for an answer.

*asked on June 4, 2007* -
## Precalc?

Suppose that Cot(theta) = c and 0

*asked on January 23, 2013* -
## Chemistry

Which of the following gases at STP would have the greatest volume? a] 1 mole of O ˇ2 b] 4 moles of He c] 0.2 moles of SO ˇ3 d] 5 moles of H ˇ2

*asked on March 30, 2020* -
## History

Which of the following are the leading theories that describe how people first arrived in North America? Select the two correct answers. A. People may have walked over a land bridge from Asia. B. People may have traveled over by boat along the Pacific

*asked on October 24, 2019* -
## Math

Find f. (Use C for the constant of the first antiderivative and D for the constant of the second antiderivative.) f ''(x) = 5/6x^5/6

*asked on October 6, 2019* -
## algebra

A photograph is 4.5 in. wide and 6 in. long. A yearbook editor has the photo reduced to fit a space of 1.9 in wide. How long is the reduced photo?

*asked on September 12, 2019* -
## math

Two less than the product of 16 and Greg's height

*asked on September 8, 2019* -
## science

The light from the Sun heats a metal surface. This is an example of A. conduction. B. radiation. C. convection. D. reflection.

*asked on January 31, 2018* -
## math

1.-3(n+5)=12 2.46=-6t-8

*asked on September 27, 2017* -
## Physics

The density of the dead sea is 1.24x10^3 kg m^-3. A wooden board with an area of 2.5m^2 is dropped in the Dead Sea. Calculate the proportion that would float above the surface. Density of wood= 800kg m^-3

*asked on May 3, 2017* -
## math

Hi I wanted to check my work for this problem. Consider the points A(1,0,0) B(2,2,2) and C(0,2,1). 1) Find the vector CA x CB I got -2i -3j +4k for this 2) Find an exact value for the area of the triangle ABC. I got sqrt29/2 for this. 3) Plane II(1) is

*asked on April 19, 2017* -
## Chemistry

is the flame coloration a test for the metal or for the acid radical?

*asked on April 18, 2017* -
## vector calculus

Hi, I'm having trouble answering this question. The lines l1 and l2 are defined as l1: (x-1)/3 = (y-5)/2 = (z-12)/-2 l2: (x-1)/8 = (y-5)/11 = (z-12)/6 The plane j contains both l1 and l2. Find the Cartesian equation of j.

*asked on April 18, 2017* -
## Math

Henry needs to cut a 4 2/3 foot board into 5 equal pieces. How long was each piece?

*asked on January 24, 2017*