38) -first you have to subtract 4-2=2
 -then solve for 2^5=32
 -subtract 32-20=12
 -and finally multiply 12*3=36
40) -you have to solve for the numerator and denominator first
 -the denominator is simple because you just have to do 2^3 which is 8
 -to solve for the numerator you have to do what's in the parentheses first (3^4-7^2) which gives you 32
 -the equation you should have now is 22+1^3+32 all divided by 8
 -1^3 just equals 1and then you just solve for the numerator
 -to solve for the numerator you have to add 22+1+32 which gives you 55 as the numerator
 -since 55 cannot be divided by 8, your answer will be 55/8 or 6.875
42) -first you have to solve for the parentheses in the brackets so solve for (67-2^6) which equals to 3
 -now your numerator should look like this: 2[8+(3)^3]
 -you have to solve for 3^3 which is 27
 -now you solve what you have left in the brackets [8+27] =35
 -multiply 2*35 which gives you 70
 -70 cannot be divided by 9 so your answer is 70/9 or 7.777777778