Решим данные выражения по порядку:
a) $$3 \times 10 - 6 = 30 - 6 = 24$$
b) $$8 + 8 \times 4 = 8 + 32 = 40$$
c) $$9 + 40 \div 4 = 9 + 10 = 19$$
d) $$54 \div 6 - 6 = 9 - 6 = 3$$
e) $$5 \times 9 - 3 \times 5 = 45 - 15 = 30$$
f) $$7 \times 6 + 36 - 6 - 4 = 42 + 36 - 6 - 4 = 78 - 6 - 4 = 72 - 4 = 68$$