Answer:
A) 277 million years
Step-by-step explanation:
Here, decay of U-238 is first order reaction. (since most of the nuclear decays are first order).
so, the equation t = 
× ln(
)
where, t = time from start of reaction
k = reaction constant
A(0) = initial concentration; A = present concentration.
⇒ 4.5 billion = 4500 million years = × ln2.
Now, given 95.82% of parent U-238 isotope is left.
⇒ t = × ln()
t = 
× ln(
)
⇒ t ≅ 277 million years.
<h3>Given</h3>
- room height is x feet
- room length is 3x feet
- room width is 3x feet
- a door 3 ft wide by 7 ft tall
<h3>Find</h3>
- The net area of the wall, excluding the door
<h3>Solution</h3>
The area of the wall, including the door, is the room perimeter multiplied by the height of the room. The room perimeter is the sum of the lengths of the four walls.
... gross wall area = (3x +3x +3x +3x)·x = 12x²
The area of the door is the product of its height and width.
... door area = (7 t)×(3 ft) = 21 ft²
Then the net wall area, exclusive of the door is ...
... net wall area = gross wall area - door area
... net wall area = 12x² -21 . . . . square feet
1 cm = 45 km
x cm = 135 km
135/45 = 3 cm
distance between the towns on the map is 3 cm.
i hope this helps :)
Answer:
A unit of volume equal to that of a cube having sides each one decimetre in length, equal to 10-3 cubic metres and 1 litre. Commonly used in fluid measure and for engine sizes.
Answer:
Each person get less than 1 cup of cider.
Step-by-step explanation:
1. Calculate the amount of cider served to each person:
Total amount of cider is 48 fluid ounces
Gus serves 7 people
Let Q the amouunt of cider served to each person:
Then, each person recived 6.85 fluid ounces of spiced cider.
2. Calculate the number of cups served:
Considering that 1 cup=8 fluid ounces, then:
That means that each person recived 0.85 cups of spiced cider.
Each person get less than 1 cup of cider.
