Rosa is trying to figure out which units to use to time her 100-meter race. Which units should she use?

A. seconds
B. minutes
C. kilograms
D. hours

Sara is creating an experiment. her hypothesis states the following. if i increase the air in my tires, then i will get better gas mileage. if this is her hypothesis what column titles do we need in our date table? a. air pressure in tire (psi) and gas mileage (mph) b. air pressure in the atmosphere (psi) and gas mileage (mph) c. miles (m) and gallons per mile (g) d. old battery and new battery

Which of these questions might a character ask if the conflict is man versus self? a. which path should i take to better myself? b. which boulder will be too heavy for me to carry? c. which friend is going to ditch me today? d. all of the above

Aresistor with an unknown resistance is connected in parallel to a 9 ω resistor. when both resistors are connected in parallel to an emf source of 21 v, the current through the unknown resistor is measured with an ammeter to be 4 a. what is the resistance of the unknown resistor? answer in units of ω.