Solve the following conversion problems: 1.1.1 Calculate the total weight of 12 eggs in kg, given each egg weighs 51.5g. 1.1.2 Convert 2 3/4 teaspoons to ml, given 1 tsp = 5ml. 1.1.3 Convert 625ml to

Each egg weighs 51.5 grams.
Total weight in grams $= 12 \text{ eggs} \times 51.5 \text{ g/egg}$

There are 1000 grams in 1 kilogram.
Total weight in kilograms $= \frac{618 \text{ g}}{1000 \text{ g/kg}}$

The total weight of 12 eggs is $\boxed{\text{0.618 kg}}$

1.1.2

Volume in ml $= 2.75 \text{ teaspoons} \times 5 \text{ ml/teaspoon}$

1.1.3

To convert 625 ml to cups, divide the volume in ml by the volume of one cup in ml.
Number of cups $= \frac{625 \text{ ml}}{250 \text{ ml/cup}}$

625 ml is $\boxed{\text{2.5 cups}}$

1.1.4

The oven temperature is $150^\circ\text{C}$.

The formula is $^\circ\text{C} = (^\circ\text{F} - 32^\circ) \div 1.8$.
Substitute $150^\circ\text{C}$ into the formula:

Multiply both sides by 1.8:

Add 32 to both sides:

The oven temperature in Fahrenheit is $\boxed{\text{302}^\circ\text{F}}$

1.1.5

Start time = 11:35 am.
Baking duration = $1\frac{1}{2}$ hours = 1 hour and 30 minutes.

Add 1 hour to 11:35 am:
11:35 am + 1 hour = 12:35 pm.
Add 30 minutes to 12:35 pm:
12:35 pm + 30 minutes = 1:05 pm.
The cake will be ready at $\boxed{\text{1:05 pm}}$

1.1.6

One cake requires 250 ml of whipped cream.

Total whipped cream in ml $= 15 \text{ cakes} \times 250 \text{ ml/cake}$

There are 1000 ml in 1 litre.
Total whipped cream in litres $= \frac{3750 \text{ ml}}{1000 \text{ ml/L}}$

To make fifteen cakes, $\boxed{\text{3.75 litres}}$ of whipped cream will be required.