What inequality expression is this

≥

Step-by-step explanation:

First, let me clarify what the inequality expressions are and what they signify.

≥ means greater than or equal too

≤ means less than or equal too

< means less than

> means greater than

The text says students in middle school must be 10 years or older. That gives me a clue that students in middle must be either 10 years old, or older than ten years old. Greater than 10, or equal to ten. The inequality symbol that compliments that is the greater than or equal to symbol, ≥. So, the inequality symbol that goes with the text is the greater than or equal to sign, ≥.

b.-4 units

all you   do is count how many times you move