Try to start by reading the manual it came with. If it didn't come with a manual, then your teacher in school will teach you how to use it for specific commands. Otherwise it's just like using a regular calculator but with the ability to do more things, what do you need to know on it?
Answer:
b
Step-by-step explanation:
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Answer:
D
Step-by-step explanation:
The expression is 
We can follow the rule of "PEMDAS" here.
PEMDAS = Parenthesis, Exponents, Multiply, Divide, Add, Subtract
So, we first need to deal with Parenthesis. Next,
There aren't any exponents, so we deal with Multiplication of 7 and 3.
Then addition/subtraction.
Hence, the first step, from the answer choices, would be D, multiply 7 and 3