A boat is heading towards a lighthouse, where London is watching from a vertical distance of 107 feet above the water. London measures an angle of depression to the boat at point A to be 14 degrees At some later time, London takes another measurement and finds the angle of depression to the boat (now at point B) to be 31 degrees . Find the distance from point A to point B. Round your answer to the nearest foot if necessary.

answer is x<

the largest number of the four options is 1.8 x 10-2

you have it in scientific notation.

1.80 x 10-6   = 0.00000180

1.80 x 10-4   = 0.000180 (bigger, or "less small", than the former one)

so

1.8 x 10-2       = 0.0180. as you see. the "less small", or the biggest one of them all.

as you have negative exponent, it means you are dividing 1.8 by 100 (i.e. moving the dot towards left, two times).

if you had positive exponent for the scientific notation, power of tenths, you would be multiplying times 100 (moving the dot towards right) as below:

1.8 x (10)2 = 180

so. if you have negative exponent in scientific notation, move the dot toward left. if it is positive, toward right as many times the exponent tells you.

open side up . . 1/50 . . 2%

closed side up . . 5/50 . . 10%

landed on side . . 44/50 . . 88%