You are given directions to a friend’s house from your school. They read: “Go east one block, turn north and go 4 blocks, turn west and go 1 block, then go south for 2 blocks.” Using your school as the origin, draw a map of these directions on a coordinate plane. What are the coordinates of your friend’s house?

(0,2)

Explanation:

Take origin (0,0) as point A and when you move one block east to point B then coordinates becomes (1,0)

Now you move 4 blocks north to point C then the coordinates of point C becomes (4,1)

Similarly, You move 1 block west to point D such that its co-ordinates becomes (0,4)

Finally you move from D to E, 2 blocks south such that point E becomes (0,2)

So, E is the friend's house and its coordinates are (0,2)

It can be diagramatically be represented by figure given below

answer: the correct answer is 1.

explanation: there are various process in which a radioactive nuclei decays:

1) alpha decay: in this process, a heavier nuclei decays into lighter nuclei by releasing alpha particle. the mass number is reduced by 4 units.

2) electron capture: in this decay process, a parent nuclei absorbs an electron and gets converted into a neutron. simply, a proton and an electron combines together to form a neutron. mass number does not change in this process.

3) gamma ray emission: it is a decay process in which an unstable nuclei gives excess energy by a spontaneous electromagnetic process. this decay releases . this process does not change the mass number.

4) positron emission: it is a type of decay process, in which a proton gets converted to neutron and an electron neutrino. this is also known as -decay. in this the mass number remains same.

from the above information, we see that only alpha-decay is producing a change in the mass number of the nucleus.

frequency or wavelenth of em radiation in a vacuum