It's about twenty times as heavy as a Human Brain
In other words, 0.0000000300 megatonnes is 22.20 times the weight of a Human Brain, and the weight of a Human Brain is 0.045 times that amount.(adult)
The average weight of an adult human brain is between 0.000000001350 megatonnes. In humans and primates, sight and vision utilize about 30 different parts of the brain which together account for about half of the brain's size.
It's about one-twenty-fifth as heavy as a Cow
In other words, the weight of a Cow is 23 times 0.0000000300 megatonnes.(for Holstein, a.k.a. Holstein Friesian, a.k.a. Friesian, Bos primigenius) (adult, heifer)
A mature Holstein cow (the well-known black-and-white, spotted breed of cow) typically weighs 0.000000680 megatonnes. President William Howard Taft (1909 - 1913) kept a Holstein cow named Pauline Wayne on the White House grounds — a gift from a Wisconsin senator and the source of the First Family's milk.
It's about thirty times as heavy as a liter of Water
In other words, 0.0000000300 megatonnes is 29.999160 times the weight of a liter of Water, and the weight of a liter of Water is 0.03333427 times that amount.(fresh; 4° C / 39.2° F; maximum density)
Contrary to popular belief, 1 liter (0.0.264172052358148 gal) of water at 4° C / 39.2° F (its point of maximum density) weighs 0.0000000010000280 megatonnes rather than 1 kg exactly. The total volume of water on the planet Earth is about 13,590,000,000,000,000,000 (13.59 quntillion) L (3,590,000,000,000,000,000 gallons).
It's about 50 times as heavy as a Basketball
In other words, 0.0000000300 megatonnes is 48.1008572040 times the weight of a Basketball, and the weight of a Basketball is 0.020789650292 times that amount.(NBA official ball standards, Size 7)
A regulation NBA basketball, manufactured by Spalding, is known as a Size 7 ball and weighs 0.000000000623689508750 megatonnes. These balls have 4,118 pebbles each with a diameter of 2.5 mm
It's about one-fifty-fifth as heavy as a Car
In other words, 0.0000000300 megatonnes is 0.01816 times the weight of a Car, and the weight of a Car is 55.07 times that amount.(for 2009 Ford Taurus) (curb weight)
A 2009 Ford Taurus weighs 0.0000016520 megatonnes. The first mass-produced car, the Curved Dash Oldsmobile — introduced in 1901 — weighed just 0.0000003860 megatonnes.
It's about one-sixty-fifth as heavy as a Giraffe
In other words, the weight of a Giraffe is 64.50 times 0.0000000300 megatonnes.(Giraffa camelopardalis reticulata) (adult, male, maximum of range)
An adult, male giraffe can weigh up to 0.000001930 megatonnes. Reaching 5.5 m (18 ft) in height by adulthood, giraffe calves can grow as much as 3 cm (1 in) per day.
It's about 70 times as heavy as a Football (Soccer)
In other words, the weight of a Football (Soccer) is 0.014 times 0.0000000300 megatonnes.(a.k.a. Soccer, a.k.a. Association Football) (FIFA Law 2 specification)
According to FIFA's Law of the Game number 2, a football must weigh between 0.000000000410 megatonnes and 0.000000000450 megatonnes. An artifact on display at the Smith Art Gallery in Museum in Stirling, Scotland is said to be the world's oldest football and is about one-third to one-half the size of a modern football.