struggling on this one may i please get some help

Answer:
diameter 12.81 units to the hundredths
Step-by-step explanation:
Assuming O is the intersection of extensions of PS and QR, at the circumference of T.
PT is chord and TS is perpendicular to PT passing through the centre T. Therefore PS is a perpendicular bisector.
SO = 10/2 = 5
Similarly, RO = 5
Consider right triangle ORT right-angled at R
radius = OT = sqrt(OR^2+RT^2) = sqrt(5^2+4^2) = sqrt(41)
Therefore diameter = 2sqrt(41) = 12.806 (to the third decimal place)