# Posts by Trev

Total # Posts: 7

**Math**

william had 30 dollars. he spent one third on a book and save the rest. how much was the book and how much did he save

**Physics**

A) What is the kinetic energy of a 1200kg car traveling at a speed of 30 m/s (≈65mph)? B) From what height would the car have to be dropped to have this same amount of kinetic energy just before impact?

**statistics**

The Intelligence Quotient (IQ) test scores for adults are normally distributed with a mean of 100 and a standard deviation of 15. What is the probability we could select a sample of 50 adults and find the mean of this sample is between 95 and 105?

**Math**

A children's game has a spinner that is equally likely to land on any 1 of 4 colors: red, blue, yellow, or green. Determine the probability of spinning a red both times on 2 spins. Explain your reasoning.

**pre alg**

(-4)cubed divided by (-2)cubed -3(-5)squared I got -67 am i correct?

**Physics**

A string has a mass per unit length of 7.00x10-3 kg/m and a length of 0.230 m. What must be the tension in the string if its second harmonic has the same frequency as the second resonance mode of a 2.05 m long pipe open at one end?

**physics**

if the volume of a penny is 0.423cm cubed , how deep would a 30ft diameter swimming pool have to be to hold one billion pennies? One billion * volume penny=volumeswimming pool but volumeswimming pool is equal to height*area so calculate height