Tyler is a builder. When he makes mortar, he uses CEMENT, LIME and SAND in the ratio 1:2:8. If he makes 55 kg mortar, find how much of : a) CEMENT b) LIME c) SAND is used Note: Show your all working and steps
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Use the data on the dot plot to answer the question.how many people read for more than three hours last week? i'm on a unit test review

Ascientist wants to use a model to present the results of his detailed scientific investigation. why would a model be useful? a )because the model makes the concepts easier to understand b) because the model is easy to put together and to use c) because the model prevents other scientists from asking questions d) because the model requires the audience to pay full attention to it i don't know what to choose because between a and d a is much more likely than d because it only wants to get the attention of the audience. i'm confuse.

He mass of a single atom of carbon can be found by dividing the atomic mass (12.01 g) by 6.022 x 10^23. which is the mass of a single carbon atom, correctly written in scientific notation with the correct number of significant figures?