i need help solving this problem

A psychologist claims that the mean age at which children start walking is 12.5 months. Carol wanted to check if the claim is true. She took a random sample of 18 children and found that the mean age at which these children started walking was 12.9 months with a standard deviation of 0.8 months. It was known that the ages at which all children start walking are approximately normally distributed. Test Carols' claim using a 2% level of significance. STEP 1: Write the hypothesis statements, identify which hypothesis is the claim, and the type of test you need to complete (left-, right-, two-tail). State the level of significance. (5 points) STEP 2: Check the requirements. Calculate the appropriate standardized test statistic (two decimal places) and P-value (4 decimal places). Either show the formula you are using or state the calculator function. (8 points) STEP 3; Conclusion (make a decision) - your conclusion must include supporting evidence. (3 points) STEP 4: Complete the interpretation. (4 points)