---
author: "Write your name here"
number: STUDENT_NUMBER
title: "Homework 5"
subtitle: "Computing in Molecular Biology 1 – Molecular Biology and Genetics Department"
description: "Rehearsal for Final Exam"
date: "January 5, 2021"
output: 
  html_document: 
    number_sections: false
    self_contained: false
editor_options: 
  chunk_output_type: inline
---

# 1. Student's data
In this exercise we analyze the data stored at
<http://dry-lab.org/static/2020/cmb1/students2018-2020-tidy.tsv>. Be sure to
download and store it in your project folder.

## 1.1 Weight and height
Please draw this plot.

```{r q1}
# replace all this line (including the `#` symbol) with your answer
```

## 1.2 Weight and hand span
Please draw this plot.

```{r q2}
# replace all this line (including the `#` symbol) with your answer
```

## 1.3 Linear model
Please build a linear model describing _weight_ as a function of _hand span_. Show the coefficient of this model.

```{r q3}
# replace all this line (including the `#` symbol) with your answer
```

## 1.4 Are men taller than women?
Please draw this plot showing height depending on the individual's sex. It is useful to make sure that the `sex` column is a *factor*.

```{r q4}
# replace all this line (including the `#` symbol) with your answer
```


# 2. USA COVID-19
Please download the data about COVID. You can use the official data from WHO or the copy in the course's webpage.

## 2.1 USA new cases
Please draw this plot.

```{r q5}
# replace all this line (including the `#` symbol) with your answer
```

## 2.2 New cases in USA between September and December
Please create a new data frame, called `Sep_to_Dec_USA`, containing the observations for US between September 1st and December 19th (inclusive). Then draw this plot.

```{r q6}
# replace all this line (including the `#` symbol) with your answer
```

## 2.3 Semilog plot
Please draw this plot using the data in `Sep_to_Dec_USA`.

```{r q7}
# replace all this line (including the `#` symbol) with your answer
```

## 2.4 Average growth rate between September and December
Using again the data in `Sep_to_Dec_USA`, please build a linear model and calculate the growth rate of _New cases_ in the relevant period.
Please write the growth rate as the daily percentage of increase.

```{r q8}
# replace all this line (including the `#` symbol) with your answer
```
