Convergent boundary I think
Answer:
yeah. Thanks for the info! (Btw, "the the string" isn't gramatically correct.)
Given that a shape is a parallelogram, the answer that is sufficient to state that it is also a rectangle is that C. The opposite sides are parallel.
A is not enough - this would mean it is a square, not a rectangle.
Energy is calculated as power*time, so give the wattage of 1200 W (equivalent to 1200 Joules/second) and time of 30 seconds, multiplying these gives 36000 J or 36 kJ of electrical energy.
If electrical charge or current is needed: Power = voltage * current, so given the power of 1200 watts and voltage of 120 V, current is 1200 W / 120 V = 10 Amperes. Charge is calculated by multiplying 10 A*30 s = 300 C.