In order to change a 2.15 kg handcart's velocity from 1.2 m/s east to 1.8 m/s east, what's the magnitude of the impulse that
should be applied to the handcart?
a
38.7 N-s
b 12.9 N-S
2.58 N-S
d 3.87 N-s
e
1.29 N. S

Aquantity of gas has a volume of 1.5 m3 and an absolute pressure of 95 kpa. when the gas is compressed to a volume of 0.5 m3, what is the new absolute pressure of the gas? (assume that there’s no change in temperature.)

It is really hard for me right know

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.