Answer:
1000 Joules per second.
Explanation:
To lift that much grass 5 meters higher than it was before the tractor did work that is the product of the (force needed to overdo gravity) and (displacement):

Power is work over the amount of time:

Communication circuit <em>(D)</em> is becoming more common in residential electrical design and construction.
LAN Ethernet cables, outlets, and even hubs and bridges, are being built into the walls of new homes, along with the usual electrical outlet wiring, to give the owner the networking infrastructure and internet access that everybody needs now ... without stringing a mess of cables on the floor and through doors all over the house.
I have the answer for A. Since there is blockage in the ear canal, some sound waves may not be able to get through or travel as quickly so you would have trouble hearing