Simon is riding a bike at 12 km/h away from his friend Keesha. He throws a ball at 5 km/h back to Keesha, who is standing still on the side walk.

How fast would Keesha say the ball is traveling toward her?

A. 5 km/h

B. 7 km/h

C. 12 km/h

D. 17 km/h

The mechanical advantage of a compound machine is equal to the one simple machine that has the greatest mechanical advantage. True or False?

The filament in a light bulb uses 2.55 amps when the voltage is 175 volts. What is the resistance?

Two scientists interpret the same set of data differently. How would the scientific community deal with this problem? A. Let the more respected scientist have his or her way B. Let the two scientists work it out between themselves C.

Energy which travels through space in the form of waves is known as A.) electrical energy B.) electromagnetic energy C.) nuclear energy D.) thermal energy

A sailboat moves north for a distance of 10.00 km when blown by a wind from the exact south with a force of 5.00 x 10^4 n. how much work was done by the wind?

Suppose it was discovered that Hubble's constant, H0, was smaller than previously thought. How would this affect our estimate of the age of the universe?

Consider six proposed properties of electromagnetic radiation: wave speeds of 3.00*108 km/s3.00*108 km/s and 3.00*108m/s3.00*108m/s, wavelengths of 673 nm673 nm and 0.221 nm0.221 nm, and frequencies of 2.39*1018 Hz2.39*1018 Hz and 4.85*1014 Hz4.

How many moles of h2 gas would be contained in 4.00 of the gas at 202.6KPa and 127c?

When a cars velocity is positive and it's acceleration is negative, what is happening to the cars motion? A) the car remains at rest B) the car speeds up C) the car travels at constant speed D) the car slows down

If blue light hits a red filter, what kind of light comes through the filter? a. red b. blue c. purple d. no light