The table below gives the number of Swedish families with children (age 0-17) living at home over the period 2014-2021. The data is divided into groups depending on the total number of children in the family. (The data below is from SCB).

Number of families with children living at home

	2014	2015	2016	2017	2018	2019	2020	2021
Children
1	470 817	472 094	475 794	480 073	484 864	488 506	492 356	494 448
2	473 340	482 034	491 863	500 520	508 409	515 536	518 857	522 202
3	133 824	137 868	142 831	146 825	150 006	151 952	152 171	153 072
4	25 905	27 150	28 810	30 393	31 365	31 783	31 657	31 755
5	6 176	6 687	7 302	7 809	8 040	8 329	8 370	8 356
6	2 210	2 254	2 473	2 675	2 788	2 800	2 733	2 628
7	790	894	928	957	1 042	1 078	1 031	929
8	353	352	393	445	421	388	356	323
9	139	147	158	152	151	123	105	114
10+	89	95	86	74	86	88	75	64

A- For each of the groups, do a scatter plot. For which cases does the plots suggest the use of a simple linear regression model?

B- Calculate estimates of the slopes and intercepts of the regression lines.

C- Calculate estimates of the standard deviations.

D- Compute the coefficients of determination. Using this as a measure, which case is best modelled by linear regression?