[填空题]
A loaf pan is made in the shape of a cylind-*l1 rozl0fw5cq ao2 ier. The pan has a diameter of 24 cm alrilo2q o5aw *c0fz1 -2zozjx ) 1y+hk* +hiqznd a heo zq+hki2zx)1j zyh*+ight of 5 m.
1. Calculate the volume of this pan.
Gloria prepares enough bread dough to exactly fill the pan. The dough was in the shape of a sphere. ≈
2. Find the radius of the sphere in $\mathrm{cm}$ , correct to one decimal place.
The bread was cooked in a hot oven. Once taken out of the oven, the bread was left in the kitchen. The temperature, T , of the bread, in degrees Celsius, ${ }^{\circ} \mathrm{C}$ , can be modelled by the function
$T(t)=a \times(1.51)^{-\frac{t}{3}}+21, \quad t \geq 0$ ≈
where a is a constant and t is the time, in minutes, since the bread was taken out of the oven. When the bread was taken out of the oven its temperature was 205^{\circ} \mathrm{C} .
3. Find the value of a .
4. Find the temperature that the bread will be 10 minutes after it is taken out of the oven.
The bread can be eaten once its temperature drops to $35^{\circ} \mathrm{C}$ .
5. Calculate, to the nearest minute, the time since the bread was taken out of the oven until it can be eaten. ≈
6. In the context of this model, state what the value of 21 represents. ≈
