Since the triangles make up a spinner, the triangles are isosceles.
The base is 2 cm and the perimeter is 10 cm.
The measure of the two legs can be determined from
2 + 2x = 10
Where is the length of the leg
Solving for x
x = 4
The area an isosceles is calculated using

where b is the length of the base
Substitute the values and multiply with the number of triangles in the spinner