Help please.
How long is between each phase of the moon?

Which object is most likely represented by a dot?

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.

Avehicle accelerates from 0 to 30 m/s in 10 seconds on a straight road