3. Suppose Earth orbited a star whose mass was double the mass of the sun. If the radius of Earth's orbit remained the same as it is now, then compared with gravitational force between Earth and the sun, the gravitational force
between Earth and the star would be -
A. half as much
B. the same
C. two times as much
D. four times as much

Suppose you increase your walking speed from 7 m/s to 13 m/s in a period of 2 s. what is your acceleration?

(2) (a) you have a simple circuit that consists of only a battery (δvbat=1.5v) and two resistors with resistance r1=10ω and r2=5ω, connected in series with each other. what is the current running through the battery? (b) you re-arrange your circuit so now r2 is attached in parallel to r1 rather than in series. what is the current running through the battery? (c) you add an additional resistor r3=7ω on the same branch as r2. what is the current running through the battery? (d) what is the power dissipated in r3?

The sound level near a noisy air conditioner is 70 db. if two such units operate side by side, the sound level near the, would bea. 70dbb. 73 dbc. 105 dbd 140 db