Symbolize the Following Argument,and Test It for Validity

Short Answer

Symbolize the following argument,and test it for validity.If valid,construct a deduction;
if invalid,assign truth values that show that the premises can be true while the conclusion is false.Use these letters:D = The drought will continue. ;S = We get an early storm. ;
M = Managers of the ski areas will be happy. ;F = There will be great fire danger next year.
If there's no early storm,the drought will continue.And if the drought continues,there will be a great danger of fire next year.So,if there is to be no great danger of fire next year,there must be an early storm.