Answer
$(a)$ $T=4°C$
$(b)$ See the image below.
$(c)$
The slope represents the rate of change of temperature for given depth.
$x$-intercept represents the point where we have temperature $0°C$.
$T$-intercept represents the temperature at the surface level.
Work Step by Step
$(a)$ $T=0.08-4$
if $x=100cm$
$T=0.08 \times 100 -4 = 8-4=4°C$
$(b)$ See the image above.
$(c)$
The slope represents the rate of change of temperature for given depth.
$x$-intercept represents the point where we have $0°C$. That is $50cm$ below the surface.
$T$-intercept represents the temperature at the surface.
