Ответ:
1.
a=float(input("a = "))
b=float(input("b = "))
l=float(input("l = "))
print("n =",a*b/l*100)
2.
a=int(input("a = "))
b=int(input("b = "))
print ("%.f" % ((a+b)/2*3)**2,";",a**3-b**3)
3.
xa=int(input("xa = "))
ya=int(input("ya = "))
xb=int(input("xb = "))
yb=int(input("yb = "))
print ("xc =","%3d" % xb," yc =",xb-xa+yb)
print ("xd =","%3d" % xa," yd =",xb-xa+ya)