3. Classify the following plants along with two main characteristics: al Cycus b) Bamboo c) Lemna d) Paddy a) Sugarcane f) Pinus g) Mango b) Mustard

A. cycas

1. it is thick and scaly

2. it grow relatively slowly and have a large, terminal rosette of leaves.

B. bamboo

1. it is very durable

2. it is both flexible and elastic

C. lemna

1. it grows as simple free-floating thalli on or just beneath the water surface

2. it are small, not exceeding 5 mm in length

D. paddy

1. it is variety purity

2. it degree of purity

E. sugarcane

1. it is bear long sword-shaped leaves

2. it's stalks are composed of many segments, and in each joint there is a bud

(newtons first law)

conservation of momentum law states :

momentum before collision = momentum after collision

momentum p (kg-m/s)= mass * velocity

say moving car=1 000 kg, velocity = 10 m/s then p = 1 000*10= 10 000 kg-m/s

say still car = 2 000 kg, velocity = 0 m/s then p = 2 000* 0 = 0 kg-m/s

total momentum prior to collision = 10 000 + 0 = 10 000 kg-m/s

momentum after collision = 10 000 kg-m/s

mass now = 1 000 kg+2 000 kg = 3 000 kg

10 000 = 3 000 kg* velocity m/s

10 000/3 000 = velocity

3.33 m/s = velocity after collision

an impulse is a force applied over time , momentum is exclusive of external forces and a perfect collision is implied