im just very confused how im supposed to enter these commands into Matlab correctly as im getting different answers each time i try something

Solve the following problems by writing commands in the command window. 1. Calculate the following a) 112+30.229.5431200 2. Define the variable x as x=8.5 and then evaluate: a) 4x314x26.32x+7.3 b) log10(x2x3)2 3. Define the variables a,b,c and d as: a=18.2,b=6.42,c=a/b and d=0.5(cb+2a), and evaluate: a) dca+b+abc(a+d)2