The researchers also found that single atoms of metal could transmit up to 100 microamperes of current. The extracted beam current is 400 microamperes and can be extracted simultaneously in any split ratio from two extraction ports on opposite sides of the cyclotron. While earlier systems required about 500 microamperes at five volts now it is less than 100 microamperes.
One acre equals 0.0015625 square miles, 4,840 square yards, 43,560 square feet or about 4,047 square metres (0.405 hectares) (see below). While all modern variants of the acre contain 4,840 square yards, there are alternative definitions of a yard, so the exact size of an acre depends on which yard it is based.
Total U.S farmland occupies 954 million acres. How many sq miles is this? [1 acre = 43,560 ft 2, 1 mi = 5280 ft] A) 1.16 X 10 21 mi 2 B)1.49X10 6 mi 2 C)6.11X10 11 mi 2 D)7.87X10 9 mi 2 E) none of the above 9.