If the simple interest on $2000 increase by $40,when the time increase by 4 years. Find the rate percent per annum. Choose the correct choice from the following:	A) 1.2%	B) 0.5%	C) 0.7%	D) 0.9%	E) 0.3%
Applying the above formula, we have   40=2000*r*4/100   r=40*100/2000*4=0.5%.   Answer is 0.5%
<result>B</result>
If the simple interest on $2000 increase by $40,when the time increase by 4 years. Find the rate percent per annum.