What is bigger 4/5 or 8/10

In triangle abc, the length of side ab is 12 cm, the length of side bc is 5 cm, and the length of side ca is 9 cm. find the measure of angle a using the law of cosines.

Select the correct answer from each drop-down menu. rewrite the formula to find voltage. the formula for electrical power (p, in watts) is where v is the voltage in volts and r is the resistance in ohms. for a particular brand of water heater, r is 32 ohms and p is 0.5 watts. the formula to find v is , and the voltage at which the heater operates is volts.

The size of a certain cell is 2.5*10^-9m. another cell is 1.5*10^3 times larger. how large is the larger cell in scientific notation?