Which of the following correctly describes the heliocentric model of the solar system? a. mars is at the center of the solar system. b. the sun is at the center of the solar system. c. the moon is at the center of the solar system. d. earth is at the center of the solar system.

(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?