I need help with 7 and 15 plsss? Thank youuu

ign a 30 KY potential differ- that moves the charge? ence and then sent through a chamber of length 18.8 cm. The time 6. | In a typical mammalian cell, the net transport by the sodium- to travel the length of the chamber was measured, with heavier potassium exchange pump that maintains the 70 mV membrane particles taking longer times. What is the travel time for a singly potential is 500 singly charged ions per second. How much ionized molecule of water? work does the pump do each second? 7. I At one point in space, the electric potential energy of a 15 nC Section 21.4 Calculating the Electric Potential charge is 45 uil. 15. I The electric potential at a point that is halfway between two a. What is the electric potential at this point? identical charged particles is 300 V. What is the potential at a b. If a 25 nC charge were placed at this point, what would its point that is 25% of the way from one particle to the other? electric potential energy be? 16. I A 2.0 cm X 2.0 em parallel-plate capacitor has a 2.0 mm spac- ing. The electric field strength inside the capacitor is 1.0 x 10* V/m. ection 21.3 Electric Potential and Conservation of Energy a. What is the potential difference across the capacitor? 8. This scanning electron microscope b. How much charge is on each plate? 17. Two 2.00 cm X 2.00 cm plates that form a parallel-plate image of a bacterium was produced capacitor are charged to + 0.708 nC. What are the electric field using a beam of electrons accelerated strength inside and the potential difference across the capacitor if through an 30 k V potential difference. the