How long can a black box survive underwater

They work to a depth of just over four kilometres, and can "ping" once a second for 30 days before the battery runs out, meaning MH370's black box stopped pinging around April 7, 2014. After Air France flight 447 crashed into the Atlantic Ocean, it took search teams two years to find and raise the black boxes.

yes we can change both the color of the value of a cell as well as background color of a cell at the same time .

as we know that excel sheet consists of columns and rows.

and intersection of column and row is called cell.

we can change color of the cell and background of the cell at the same time.

hence the statement that

can a person change color of the cell and background of the cell at the same time is true.

a.s= 230t– 110; 1500 lbc.t= 230s– 110; 1500 lbb.s= 230t+ 110; 1720 lbd.s= 199t– 110; 1280 lb