Jamal is skating on a sidewalk. his initial velocity is 0.0 m/s; 35 seconds later his velocity is 5.0 m/s. what is his acceleration? -0.14 m/s/s -7 m/s 0.14 m/s/s 7 m/s

Can anybody me with this? ? (picture included.)

Water is siphoned from a large tank and discharges into the atmosphere through a 50-mm diameter tube. the end of the tube is b = 2.1 m below the tank bottom which is a = 7.4 m deep, and viscous effects are negligible. determine the maximum height h over which the water can be siphoned without cavitation occurring. atmospheric pressure is 101.4 kpa, and the water vapor pressure is 1.79 kpa (absolute)

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.