When two electrical resistors with resistance r1 > 0 and r2 > 0 are wired in parallel in a circuit, the combined resistance r, measured in ohms (ω), is given by 1 r = 1 r1 + 1 r2 (a) find ∂r ∂r1 and ∂r ∂r2 after solving for r (e. g., r = . (b) describe how an increase in r1 with r2 held constant affects r. (will r increase or decrease? ) (c) describe how a decrease in r2 with r1 held constant affects r. (will r increase or decrease? )

Abasketball star covers 2.65 m horizontally in a jump to dunk the ball. his motion through space can be modeled precisely as that of a particle at his center of mass. his center of mass is at elevation 1.02 m when he leaves the floor. it reaches a maximum height of 1.90 m above the floor and is at elevation 0.910 m when he touches down again. (a) determine his time of flight (his "hang time"). (b) determine his horizontal velocity at the instant of takeoff. (c) determine his vertical velocity at the instant of takeoff. (d) determine his takeoff angle. (e) for comparison, determine the hang time of a whitetail deer making a jump with center-of-mass elevations yi = 1.20 m, ymax = 2.45 m, and yf = 0.750 m.