we know that
area of a rectangle=length*width
length=area/width
area=2.76 x 10^12 units²
width=4.6 x 10^5 units
length=2.76 x 10^12/4.6 x 10^5 ------> 6 x 10^6 units
perimeter of a rectangle=2*[length+width]
width=4.6 x 10^5 units----> is equal to 0.46 x 10^6 units
length=6 x 10^6 units
perimeter of a rectangle=2*[6x10^6+0.46x10^6]----> 12.92 x 10^6 units
the answer is
12.92 x 10^6 units