# Posts by Kate

Total # Posts: 2,048

**Precalculus**

A discus is thrown from a height of 3 feet with an initial velocity of 55 ft/s at an angle of 44° with the horizontal. How long will it take for the discus to reach the ground? I started off with 55cos(44)=40 then I made an equation 40t-16(t)=2.5 seconds? I feel like I did...

**Precalculus**

Thanks reiny! But one question how do you know when to use the triangle method and when to use parallelogram?

**math**

Thanks for answering! and yes i think there is an error in the question

**math**

Find cos x if sin x cot x = 4. I got 4 but isnt it impossible for cos to equal 4? Isnt it only supposed to range from -1 to 1? the answer choices are 1)4 2)2 3)1 4)sqrt 2

**math**

So i need to figure out what the angle and speed was of a foot ball that traveled 59 yards how can i figure that out? what formula can i use?

**physics**

which of the following is there no net work? A car accelerates down a hill. A car travels at constant speed on a flat road. A car decelerates on a flat road. A car decelerates as it travels up a hill. I say its the first one

**Math-please help!!**

Normally, the first 3 key points of a sine curve are (0,0), (90,1), and (180,0). If the function is changed to y=-2sin(3x-120)+5, the key points given above change to... Please explain this to me so that I can do it myself.

**biology**

from the phenotype of the kernals on each P generation cob what would the predicted genotype of any F1 plant be?

**biology**

Based on what you know about phenotypes and figure 2 for the p generation what is the corn plant genotype on each cob containing the P corn kernals

**maths**

simplify 12-1/9 /4/3+(1/2)^2

**Math**

How long will it take for a 1 g sample of Polonium 210 to lose all but 1/28 of its radioactivity if the half-life is 140 d?

**Math**

How long will it take for a 1 g sample of Polonium 210 to lose all but 1/28 of its radioactivity if the half-life is 140 d?

**Math**

In a recent dig, a human skeleton was unearthed. It was later found that the amount of 14C in it had decayed to (1/rt8) of its original amount. If 14C has a half life of 5760 years,how old was the skeleton?

**Math**

In 1976 a research hospital bought half a gram of radium for cancer research. Assuming the hospital is still exists, how much of this radium will the hospital have in the year 6836 if the half-life of radium is 1620 years?

**Math**

In 1976 a research hospital bought half a gram of radium for cancer research. Assuming the hospital is still exists, how much of this radium will the hospital have in the year 6836 if the half-life of radium is 1620 years?

**Math**

y=-x^2+1.5x+2 Find the maximum value.

**Math**

What are some examples of exponential function (Using the formula: Al = A0(1/2)^t/h ), trig functions that are used to find amplitude, period, max, min etc., and combinations of transformation at home or in life in general?

**Math**

Use the information provided to write the vertex form equation of each parabola. a)y + 60x + 294 = -3x^2 b)−(y+1) = (x−4)^2

**Math**

A piece of cardboard has a length of 60cm and a width of 40cm. In order to make the cardboard into an open box, a box with no lid), a piece of length x must be cut out of each corner. Write an equation to represent each dimension of the box.

**Math**

Simplify: (3x+5)^3-3x(x^2-1)

**Math**

If f(x)=5x+2 and g(x)=x^2+3, then what is f(g(x))?

**Math**

Which of the following is a solution to the trigonometric equation 2cos2 x - 5cos x + 2 = 0? A) 240 degrees B) 135 degrees C) 270 degrees D) 90 degrees

**Math**

Identify the period in degrees and radians: y = sin2x: y = cos(3/2)x: y = 2sin(1/2)x: y = 1.5cos0.25x:

**Math**

Given that the formula is y=-9cos12x+9 What is k in radian?

**Math**

Time Height above ground 0 45 3 65 6 80 9 85 12 80 15 65 18 45 21 25 24 10 27 5 30 10 33 25 36 45 I know the following things: The minimum is 5 while the maximum is 85. amplitude: 85-5/2 = 40 period =360/45 = 8 vertical translation = 5 + 40 = 45 But I can't seem to get the...

**Math-please help!!**

Make a word document with the key points (in tables/charts) for the following functions, given in the form y=asink(x+d)+c Start with multiplication/division (multiply ‘y’ by a, divide ‘x’ by k) Then add c to the y values, subtract d from the x values 1.y=...

**Math**

1) Find three functions with unlimited domains and ranges. 2) Find two functions with restricted domains. 3) Find two functions with restricted ranges. Im confused as to how I can find the answer for these question, can you please explain along the steps.

**Math**

A ski resort is installing tows on its new ski runs. The baby hill has a vertical height of 500.0 m and is inclined at 42o. Determine the appropriate length of the T-bar cable if it goes to the top of the hill and returns.

**Math**

A football player is attempting a field goal. The angle formed by the player's position on the field and the line of sight to each upright is 33o. If the distances to the uprights are 7.5 m and 10.0 m, calculate the width of the uprights.

**Math**

Prove each identity: a) 1-cos^2x=tan^2xcos^2x b) cos^2x + 2sin^2x-1 = sin^2x I also tried a question on my own: tan^2x = (1 – cos^2x)/cos^2x R.S.= sin^2x/cos^2x I know that the Pythagorean for that is sin^2x + cos^2x That's all I could do.

**Math**

Prove each of the following identities. a)tan^2x = 1 – cos^2x/cos^2x b)sinx/1 – sin^2x = tanx/cosx

**Math**

Solve for all possible values of x where O°≤x360°. sin x=2/3.

**Math**

Solve for all possible values of x where O°≤x360°. sin x=2/3. I do not understand these types of questions please answer in as much detail as you can so I can do them myself.

**Math**

Solve for all possible values of x where O°≤x≤360°. tan x = -1/√3 cos x = 1/2

**Math**

Determine the EXACT values of each of the following: a) sin 240° b) cos 135°

**Math**

Find the angle (Θ) for a terminal arm with the following coordinates(round to one decimal place): (5,8)

**Math**

What are some examples of acute and obtuse triangles in a home?

**Math**

Determine the exact value of: sin30° + cos225° + sin150° + cos330°

**Math**

The winner of a popular lottery is offered one of two options: i) a lump sum of $102 500 ii) $1000 every month for 10 years If the money can be invested at 3.0% p/a, compounded monthly, which option should the winner choose? Justify your reasoning. Every three months, Carlos ...

**Math**

How much would you have to invest at 6.3% interest for it to have grown to $67.06 in five years

**Math**

That can't be right...the correct answer shows it should be 12 years.

**Math**

You invest $25 in an account earning 7.5% interest per year. After how many years is it worth $42.50?

**Math**

Sam gets deposits a total of $3500 every three months to the bank which earns a 6.5% p/a. After five years how much will he have in his account? Ren wants to buy a new car that costs $26255, so, he would deposit money into his savings account with an interest rate of 3.9% p/a ...

**Math**

Stacey buys a $1000 RRSP today. After one year she adds $2500. By the end of the second year, the money has grown to $3851 as it has earned interest over time. What rate of interest does the money earn? 1000x^2 + 2500x - 3851 Use the quadratic formula above and your calculator...

**Math**

Determine the present value of the annuity: $1500 at the end of each 3-month period, for 5 years, at 4.5% p/a, compounded quarterly

**Math**

Imagine you have invested $500 in an account that pays 5% simple interest per year. Can you find an arithmetic sequence to look for the amount of money in the account after 20 years?

**Physics**

If you go to google and type "conservation of momentum photogate lab penn state" this is just like the experiment we performed. It should be the top result "Physics 250 Laboratory: Conservation of Momentum. Hope this helps.

**Physics**

So I had an exam today and one of the questions is bugging me. Our professor is out of town for a few days, so we had a proctor and I still can't figure it out using my notes. It was a question about two carts and deals with momentum. Cart A is at rest between two ...

**Physics**

So I had an exam today and one of the questions is bugging me. Our professor is out of town for a few days, so we had a proctor and I still can't figure it out using my notes. It was a question about two carts and deals with momentum. Cart A is at rest between two ...

**Math**

tn - tn-1 = 2n + 3; t1 = 10 Find the first five terms in the sequence using this recursive formuls

**Math**

tn - tn-1 = 2n + 3 Find the first five terms in the sequence using this recursive formuls

**chemistry**

How many grams of acetic acid (MW = 60 g/mol, pKa=4.75) are needed to change 1000 L of water with a pH of 11 to a pH of 5.5?

**MATH**

Halley's comet appears in the sky approximately once every 77 years. If the comet was seen in by Astronomer Edmund Halley in 1531. How many times has the comet been spotted since?

**chemistry**

How many grams of HCl are needed to change 1000 L of water with a pH of 11 to a pH of 5.5?

**PHYSICS**

A 240 g block on a 41 cm-long string swings in a circle on a horizontal, frictionless table at 73 rpm. (a) What is the speed of the block? (b) What is the tension in the string?

**physics**

A 5.0 m diameter merry-go-round is initially turning with a 4.6 s period. What is the speed of a child on the rim?

**Math(Pre=Calc)**

The first term in a sequence of number is t1 = 4. The terms that follow are defined by the formula: tn - tn-1 = 3n -2. Determine the value of t50.

**physics**

A penguin sliding on ice has an initial velocity of 5 m/s due north. Due to a strong wind, the penguin has an acceleration of 2 m/s2 SE. What is the penguin’s displacement (magnitude and direction) after 4 seconds

**physics**

Three forces act on a 3 kg box: 10 N South-west, 17 N North-west, 5 N due East. What is the acceleration of the box?

**physics**

You throw a ball downwards with a speed of 10 m/s. It hits the ground 4 meters below from where you threw it. How long is the ball in the air and what is the ball’s velocity just before it hits?

**physics**

A .5 m long, 3 cm diameter metal bar has a Young’s Modulus of 7.0x1010 N/m2. If a 50,000 N force is applied to the end of the bar, by how much will it compress?

**speech**

it has to be one describing word but i need two more and those websites were no help to me

**Algebra 2**

what number did they give you because you have to plug the answer in for X these are two differnt parts. The question is say use X+5 if x is greater than 0 or the answer is three if x is less than 0

**physics**

A 3.0 m tall, 42 cm diameter concrete column supports a 230,000 kg load. By how much is the column compressed? Assume Young's modulus for concrete to be 3.0 1010 N/m2. in mm

**PHYSICS**

a 10cm long spring is attached to the ceiling. when a 2.6kg mass is hung from it, the spring stretched to a length of 15cm. what is the spring constant k how long is the spring when a 4.0 kg mass is suspended from it

**physics**

a skater holds her arms outstretched as she spins at 140 rpm. What is the speed of her hands if they are 125 cm apart?

**Physics**

A 36 kg box hangs from a rope. What is the tension in the rope if the following are true? (a) The box moves up a steady 5.0 m/s? (b) The box has vy = 5.0 m/s and is slowing down up at 5.0 m/s2?

**physics**

thank you!

**physics**

A 20 kg crate is placed on a horizontal conveyor belt. The materials are such that μs = 0.6 and μk = 0.3. (c) What is the maximum acceleration the belt can have without the crate slipping? (d) If acceleration of the belt exceeds the value determined in part (c), what...

**physics**

How much force does an 60 kg astronaut exert on his chair while accelerating straight up at 8m/s squared?

**physics**

How much force does an 60 kg astronaut exert on his chair while accelerating straight up at 8m/s squared?

**PHYSICS**

A 900 kg car pushes a 1900 kg truck that has a dead battery. When the driver steps on the accelerator, the drive wheels of the car push against the ground with a force of 4800 N. (a) What is the magnitude of the force of the car on the truck? (b) What is the magnitude of the ...

**PHYSICS**

Zach, whose mass is 67 kg, is in an elevator descending at 12 m/s. The elevator takes 3.5 s to brake to a stop at the first floor. (a) What is Zach's apparent weight before the elevator starts braking? (b) What is Zach's apparent weight while the elevator is braking?

**physics**

King Arthur's knights fire a cannon from the top of the castle wall. The cannonball is fired at a speed of 54 m/s and at an angle of 34°. A cannonball that was accidentally dropped hits the moat below in 1.1 s.(a) (a)How far from the castle wall does the cannonball hit...

**physics**

A supply plane needs to drop a package of food to scientists working on a glacier in Greenland. The plane flies 92 m above the glacier at a speed of 135 m/s. How far short of the target should it drop the package?

**physics**

A go-cart has an initial speed of 23.4 m/sec. Fifteen seconds later the go-cart has a final speed of 36.8 m/sec. What is the magnitude of the go-cart's displacement?

**algebra**

How do I write this number in scientific notation 1. 8.68x10^1 2.1,900,000

**Physics**

A bullet with mass 4.91 g is fired horizontally into a 1.981-kg block attached to a horizontal spring. The spring has a constant 6.25 102 N/m and reaches a maximum compression of 6.38 cm. a) find the initial speed of the bullet-block system. b) find the speed of the bullet

**Biostatistics**

here is some evidence to indicate that the null hypothesis is incorrect

**Pre-Calc**

1. Square both sides. (x+5)^5=(x+5) 2. FOIL the left side. x^2+10x+25=x+5 3. Subtract x and 5 from both sides. x^2+9x+20=0 4. Factor. (x+5)(x+4)=0 5. Solve using the zero product property. x+5=0 x+4=0 x=-5 and x=-4

**grammar**

Is this sentence. Mr. and Mrs. Lopez's plane tickets, incidentally were found in the lobby. Is this correct punctuation?

**finance**

47,912

**Algebra**

I could use some help on this please. Write a linear function that satisfies the given conditions: h(-1) = 4, h(0) = -5 Thanks!!!

**Physics**

In a physics lab experiment, a spring clamped to the table shoots a 18 g ball horizontally. When the spring is compressed 20 cm, the ball travels horizontally 4.9 m and lands on the floor 1.3 m below the point at which it left the spring. What is the spring constant?

**statistics**

The following data lists the average monthly snowfall for January in 15 cities around the US: 37 33 35 27 9 45 22 8 42 48 37 39 9 15 12 Find the mean, variance, and standard deviation

**calculus**

the derivative of f(x) = e^(sin x)cos(x)

**calculus**

f(x) = e^(sin(x))cos(x)

**calculus**

f(x) = e^(sin(x))cos(x)

**calculus**

i missed something in it sorry. it was ∫sec 2x tan 2x dx

**calculus**

its sec 2x

**calculus**

i don't get what you mean?

**calculus**

∫sec 2x tan x dx

**freshman chem**

if 5.00 g of ethanol is added to 15.0g of whater, what is the % concentration of ethanol in water??

**chemistry**

if 5.00g of ethanol is added to 15.0g of water, what is the % concentration of ethanol in water? THANKYOU

**English - Macbeth**

Think about Macbeth’s position at the conclusion of Act III. In what ways has his ambition, which allowed him to obtain the Scottish throne in the first place, begun to be detrimental to him? Cite specific examples from the play in your response. What does this question ...

**CHEMISTRY HELP!**

The previous answer is wrong by the way.

**math**

16-4+1 = 13 13 to the 2nd power = 13 *13 13 * 13 = 169

**English**

I just finished reading Macbeth for school. My teacher assigned a essay for us to do. She asked if we think the witches' predictions were right or if the witches' predictions were disappointing because of duality and doublespeak. I said that I believe in neither and I ...

**math**

the answer ie 30

**Math**

$307,$330,$440,$405 (range