# R_scott

Popular questions and responses by R_scott
1. ## Chemistry

volume is directly proportional to the absolute (Kelvin) temperature and inversely proportional to the pressure v = 20 L * [(new temp.) / (old temp.)] * [(old press.) / (new press.)]

posted on July 1, 2020
2. ## Physics

...teach the group?? the range is ... R = [v^2 * sin(2Θ)] / g ... v is the launch velocity ... 200 m/s ... Θ is the launch angle ... 30º

posted on July 1, 2020
3. ## Mathematics

each team will play four games...one with each of the four other teams there are ten games in total ... five teams each playing four games ... 5 * 4 = 20 ... but ...A playing B is the same as B playing A ... so ... 20 / 2 = 10

posted on June 30, 2020
4. ## Mathematics.

volume is, the area of the cross-section, multiplied by the length v = [π * 3.5 cm)^2] * 8 cm

posted on June 29, 2020
5. ## math

the two dice are independent events ... the probability of both occurring ... is the product (multiply) of the individual probabilities p = (6 / 26) * (3 / 12) remember to reduce fractions where possible

posted on June 29, 2020
6. ## physics

momentum is conserved .125 kg * 25.0 m/s = (.125 kg + .101 kg) * v solve for the horizontal velocity (v) of the arrow/apple the flight time of the arrow/apple is the time it takes to fall 1.85 m 1.85 = 1/2 g t^2 ... solve for the flight time (t) the

posted on June 29, 2020
7. ## Math

if the bases are the same , you can add the exponents (2/9)^3 × (2/9)^(-6) = (2/9)^(3-6) = (2/9)^(-3) (2/9)^(-3) = (2/9)^(2m - 1)

posted on June 29, 2020
8. ## Physics

Δh = [1/2 * (-9.81 m/s^2) * (2.00 s)^2] - (15.0 m/s * 2.00 m)

posted on June 26, 2020
9. ## Physics

11.26 m = 1/2 * g * (3.17 s)^2

posted on June 26, 2020
10. ## Physics

h = [1/2 * (-9.81 m/s^2) * (0.250 s)^2] + (.250 s * 5.00 m/s) + 40.0 m

posted on June 26, 2020
11. ## Physics

the accelerations are the same the velocities are different

posted on June 26, 2020
12. ## math

the sides are unchanged

posted on June 26, 2020
13. ## math

if two cups is one pint , how many pints is five cups?

posted on June 25, 2020
14. ## Physics

20 * 377 * (200 - t) = [(50 * 4190) + (60 * 377)] * (t - 30)

posted on June 25, 2020
15. ## geometry

the radius of the base is ... 18 cm * (300º / 360º)

posted on June 25, 2020
16. ## math

8 oz = 1 C 2 C = 1 pt 2 pt = 1 qt 4 qt = 1 gal

posted on June 25, 2020
17. ## mathematics

the parabola ... y = x^2 the line ... y = 2 x + 3

posted on June 25, 2020
18. ## math

56 kg * 9.8 m/s^2 * 1.0 m / 1.4 s = ? Watts

posted on June 25, 2020
19. ## geometry

yup

posted on June 25, 2020
20. ## Probability

\$65k is 1.2 s.d. above the mean use a z-score table to find the % (probability) this represents

posted on June 24, 2020
21. ## math

(s + 6) * 2 = 26

posted on June 24, 2020
22. ## science

balancing ... 2 HCI + Na2CO3 = 2 NaCI + H20 + CO2

posted on June 24, 2020
23. ## Physics

mass of the block = volume * density force (weight) = m * g pressure = force / area ... newton per m^2 is a Pascal max pressure when resting on smallest side ... 1.2 m x 1.0 m min pressure when resting on largest side ... 1.2 m x 1.5 m

posted on June 24, 2020
24. ## Physics

power = work / time = m g h / t = 75 kg * 9.8 m/s^2 * 12 * .20 m / 10 s = ? W

posted on June 24, 2020
25. ## Physics

the platform height is one significant figure all of the responses are at least two significant figures

posted on June 23, 2020
26. ## Math

taking natural log ... x ln(10) = ln(2) + 1

posted on June 22, 2020
27. ## Mathematics

sin(B) / sin(A) = b / a C = 180º - A - B c = b * sin(C) / sin(B)

posted on June 21, 2020
28. ## geometry

joining the midpoints means that the smaller triangle is half the height ... and half the base length of the larger triangle use the triangle area formula to find the relationship k * [1/2 * (b/2) * (h/2)] = 1/2 * b * h ... solve for k

posted on June 18, 2020
29. ## Math

5.4% is lost to leakage ... so (100% - 5.4%) remains in the tank 1500 L * (100% - 5.4%) = ?

posted on June 18, 2020
30. ## Physics

a. the work is equal to the initial kinetic energy of the block ... K.E. = 1/2 m v^2 = 1/2 * 4.0 kg * (6.0 m/s)^2 = ? Joules b. work = force * distance ... distance = (answer a.) / 88 N = ? m

posted on June 18, 2020
31. ## Math

find f(x) for the values at the ends of the interval divide the difference in the f(x) values by the difference in the x values

posted on June 18, 2020
32. ## Physics

2E4 C/s * 1E-4 s = ? C ? C / 1.6E-19 C/e = ? e

posted on June 18, 2020
33. ## Math

use the quadratic formula to find the roots of the 1st equation then plug the numbers into the 2nd question

posted on June 18, 2020
34. ## Math

\$20 * .06 * 2000

posted on June 17, 2020
35. ## Physics

1. yes ... 250 J is correct 2. kinetic energy = work ... 1/2 * m * v^2 = f * d ... find the work , then solve for the velocity ... 5 m/s seems correct ... maybe a significant figure issue? 3. similar to #2 ... work on the rocket is "net force" multiplied

posted on June 17, 2020
36. ## Calculus

(a) differentiating ... f'(x) = -0.2 x - 0.7 (b) to find dp/dx , plug x=3 into f'(x)

posted on June 17, 2020
37. ## mathematics

5% semiannually means 2.5% per compounding period balance = 500 * [1 + (2.5%)]^(6 * 2) b = 500 * (1.025)^12

posted on June 16, 2020
38. ## Mathematics

18 hr : 48 hr 18 / 48 = 3 / 8

posted on June 16, 2020
39. ## math

the coordinates are in alphabetical order ... x , y no +2 y-coordinate in the list

posted on June 16, 2020
40. ## mathematics

t / 1.8 cm = 84 / 350

posted on June 16, 2020
41. ## mathematics

x - 3 = k y^2 5 - 3 = 4 k ... k = 1/2 x - 3 = 1/2 * 6^2

posted on June 16, 2020
42. ## Physics

the center of mass of the rule is at the 25 cm mark 40 g * (15 cm - 2 cm) = M * (25 cm - 15 cm)

posted on June 16, 2020
43. ## Math

3rd and 4th days ... 18 km + 18 km = 36 km 36 km = 3/4 d after 1st day ... d = 48 km 48 km = 2/3 total d ... total d = 72 km G = 3 S G - 5 = 2 (S + 5) ... G = 2 S + 15

posted on June 16, 2020
44. ## Mathematics

tan(Θ) = 120 / 400

posted on June 16, 2020
45. ## mathematics

if r is a root (zero) , then x-r is a factor complex roots (containing i) occur in conjugate pairs ... if 2+2i is a root , then 2-2i is also P(x) = (x - 2 - 2i) (x - 2 + 2i) (x + 1) (x - 2) multiply the factors to find the 4th order function

posted on June 15, 2020
46. ## Chemistry

moles H2SO4 = 10 g / (molar mass H2SO4) moles H2O = 20 g / (molar mass H2O) mole fraction H2SO4 = moles H2SO4 / (moles H2SO4 + moles H2O)

posted on June 15, 2020
47. ## Trigonometry

distance between the exits is ... d1 = 81 km - 74 km road distance from balloon to x-81 ... d2 = 875.0 m / tan(11º) road distance to x-74 ... d3 = d1 - d2 angle of depression to x-74 ... tan(Θ) = 875.0 m / d3

posted on June 15, 2020
48. ## Math

sin^2(θ) = 3 / 4 ... sin(θ) = ±√3 / 2

posted on June 15, 2020
49. ## math

n-2 , n-1 , n , n+1 , n+2 , n+3 6 n + 3 = 519

posted on June 14, 2020
50. ## trigonometry

the downhill angle of the fence is 110º ... 90º + 20º using the law of sines ... sin(Θ) / 2.5 = sin(110º) / 6.3

posted on June 14, 2020
51. ## mathematics

oobleck is correct

posted on June 14, 2020
52. ## mathematics

tan(Θ) = 2.1 / 15.9

posted on June 14, 2020
53. ## Physics

heat = mass * specific heat * temperature change 25 * x * (100. - 27.5) = 85 * 4.19 j/g⋅ºC * (27.5 - 25.0)

posted on June 14, 2020
54. ## Algebra

guessing a pie with a piece missing the outside circular perimeter is 5/6 of the circumference ... 5/6 * π * 2 * 7 the inside perimeter of the mouth is 2 radii ... 2 * 7

posted on June 13, 2020
55. ## Chemistry

sample volume * molarity = moles .0284 L * 0.185 moles/L = ? moles

posted on June 11, 2020
56. ## Chemistry

to find the moles of glucose in 54.30 g , divide by the molar mass

posted on June 11, 2020
57. ## Math

2k + 8k + 10k = 180º ... k = 9º smallest angle is 2k

posted on June 11, 2020
58. ## Math

the general circle equation is ... (x - h)^2 + (y - k)^2 = r^2 (h,k) is the center of the circle , r is the radius the equations of the two points should NOT be equal ... and they should have the correct format

posted on June 11, 2020
59. ## Physics

work = force * distance 1210 = f * 20.0 ... f = 60.5 N 60.5 N = 75 N * cos(Θ)

posted on June 11, 2020
60. ## Physics

the work (energy) is the difference in kinetic energy at the two speeds work = 1/2 (62 kg + 12 kg) * [(12.7 m/s)^2 - (8.2 m/s)^2] ... Joules

posted on June 11, 2020
61. ## Math

gradient is also known as slope ... the change in y, divided by the change in x the general slope-intercept equation is ... y = m x + b ... m is the slope , and b is the y-intercept (where the line crosses the y-axis) solving the given equation for y ...

posted on June 11, 2020
62. ## mathematics

divide by e^(kt) ... y / [e^(kt)] = y0

posted on June 8, 2020
63. ## Physics

the ultraviolet end of the spectrum is higher energy than the infrared

posted on June 8, 2020
64. ## Physics

the weight (force) of a 3.15 kg mass is ... 3.15 * g find the spring constant (k) by dividing the force by the extension ... (3.15 * g) / (13.40 cm - 12.00 cm) stored energy is ... 1/2 * k * x^2 ... find x ... add it to 12 for Joules , the extension is in

posted on June 8, 2020
65. ## Science

distance and orbital velocity are inversely related the area of the orbital ellipse swept by a planet is a constant

posted on June 7, 2020
66. ## Mathematics

draw the diagram and use the law of sines

posted on June 7, 2020
67. ## Math

π * d * h ... is the lateral surface area

posted on June 7, 2020
68. ## algebra

q - 17

posted on June 6, 2020
69. ## Maths

7 * 5 = 35 ... man-days to dig hole half a hole takes 35/2 man-days (35/2) / 3 = 35/6 man-days for half a hole ... almost six days

posted on June 5, 2020
70. ## mathematics

40 * (1 - .20) * (1 + .05)

posted on June 4, 2020
71. ## mathematics

how many ways can you get 8? 6-2 ,5-3 , 4-4 , 3-5 , 2-6 there are 36 possible outcomes ... 6 sides * 6 sides

posted on June 4, 2020
72. ## science

electrostatic force is an inverse-square relation 6.0 / d^2 = 15 /(2.0 - d)^2 solve for d 15 d^2 = 24 - 24 d + 6 d^2 9 d^2 + 24 d - 24 = 0 ... 3 d^2 + 8 d - 8 = 0

posted on June 4, 2020
73. ## Physics

the ramp (frictionless) is a longer distance, but a lower effort (force) the work is the same

posted on June 4, 2020
74. ## Physics

the gravitational force is constant over this short distance the change in gravitational potential energy (work) is ... m * g * h ... the work is negative (against gravity) FYI ... technically, the answer sig fig is the smallest of the input data ... the

posted on June 4, 2020
75. ## Physics

how big is the loop?

posted on June 4, 2020
76. ## Mathematics

(105º / 360º) * 2 * 6 cm * 22/7

posted on June 4, 2020
77. ## Math

the 7 rounds up to 10 ... 1010

posted on June 3, 2020
78. ## Chemistry

3970 g / 7.86 g/mL = ? mL 100 mL = 1 dL

posted on June 3, 2020
79. ## algebra

angle + complement = 90º

posted on June 3, 2020
80. ## physics

5.00E2 N * cos(29º) * 20 m = ? Joules

posted on June 3, 2020
81. ## Physics

the centripetal force (tension in the string) ... keeps the ball moving in a circle the force necessary is ... m v^2 / r = .167 * 4.9^2 / .98 ... Newtons ... this is the tension at the sides of the circle at the top and bottom of the circle ... the weight

posted on June 3, 2020
82. ## physics

m * g * h / t = 32 kW ... m * g * h / 32 kW = t ... seconds

posted on June 3, 2020
83. ## Maths

let x = 3^n x^2 + 1 - (4 x + 4 + 9) = 0 ... x^2 - 4 x - 12 = 0 (x - 6) (x + 2) = 0 ... x = 6 , x = -2 3^n = 6 ... 3^n = -2 is an impossible solution n log(3) = log(6)

posted on June 3, 2020
84. ## physics

time = distance / rate 8 km / v = 9 km / (v + 2) multiplying by [v ( + 2)] ... 8 v + 16 = 9 v speeds are ... 16 kph and 18 kph convert to m/s ... multiply by 1000 m/km and divide by 3600 s/hr

posted on June 3, 2020
85. ## Mathematics

6 * 5/8 = ?

posted on June 3, 2020
86. ## Physics

see Bill at 6:58 yesterday

posted on June 3, 2020
87. ## Physics

your mass is ... 588 / g the force (391 N) accelerates your mass for 0.576 s find the acceleration ... f = m a ... a = f / m find the distance during acceleration ... d = 1/2 a t^2 find your final velocity ... v = a t time to shore = acceleration time +

posted on June 2, 2020
88. ## Algebra

s equals zero on the ground 0 = −16t2 + 2120 16t2 = 2120 ... t^2 = 132.5 ... this is the SQUARE of the time take the square root to find the fall time

posted on June 2, 2020
89. ## Algebra

the max is on the axis of symmetry of the parabola x = -b / 2 a = -10 / (2 * -5) = 1 1 second up, one second down ... 2 sec flight time plug one into the original equation to find max height

posted on June 2, 2020
90. ## math

D time = distance / rate = 20 km / 10 kph = 2 hr M has covered ... 20 km - 4 km = 16 km ... in 2 hr ... 16 km / 2 hr = 8 kph M has 4 km to go ... 4 km / 8 kph = 1/2 hr

posted on June 1, 2020
91. ## Physical Science

m * g * Δh = 80 kg * 9.8 m/s^2 * (700 m - 400 m) = ? Joules

posted on June 1, 2020
92. ## PreCalculus

these identities are helpful cos(u) = 1 / sec(u) cos(u/2) = ± √{[1 + cos(u)] / 2} cos(u/2) = ± √({1 + [1 / sec(u)]} / 2) ​

posted on June 1, 2020
93. ## Mathematics

h + t + u = 6 h = 2 u t = h + u ... 2 t = 6 ... t = 3 h + u = 3 ... 3 u = 3 ... u = 1 h + 3 + 1 = 6 ... h = 2

posted on May 30, 2020
94. ## Algebra

p^4 + 4 p^3 q + 6 p^2 q^2 + 4 p q^3 + q^4

posted on May 29, 2020
95. ## physics

hz = cycles / seconds

posted on May 29, 2020
96. ## physics

looks good

posted on May 29, 2020
97. ## science

bingo

posted on May 29, 2020
98. ## science

how are plant cells different from animal cells?

posted on May 29, 2020
99. ## Algebra

4000 * e^(rt) 4000 * e^.328

posted on May 29, 2020